U.S. patent application number 13/279749 was filed with the patent office on 2012-05-03 for vibration module for portable terminal.
This patent application is currently assigned to Korea Advanced Institute Of Science And Technology. Invention is credited to Yu-Dong Bae, Young-Jun Cho, Dong-Soo Kwon, Eun-Hwa Lee, Jeong-Seok Lee, Young-Min Lee, Dong-Bum Pyo, Tae-Heon Yang.
Application Number | 20120108299 13/279749 |
Document ID | / |
Family ID | 45975767 |
Filed Date | 2012-05-03 |
United States Patent
Application |
20120108299 |
Kind Code |
A1 |
Yang; Tae-Heon ; et
al. |
May 3, 2012 |
VIBRATION MODULE FOR PORTABLE TERMINAL
Abstract
Disclosed is a vibration module for a portable terminal that
includes a housing, a magnetic moving part movable in a first
direction within the housing; an elastic member supported between
the opposite ends of the magnetic moving part and inner walls of
the housing, and a solenoid coil provided in the housing. The
vibration module is positioned at one end of the moving section by
the magnetic force of the magnetic moving part and an object around
the magnetic moving part, allowing the vibration module to provide
a user with a feeling similar to a click feeling via the
acceleration produced at a stopping instant. In addition, when
vibrating, the vibration module generates sufficient vibration
power through acceleration at the instant of changing moving
direction at the ends of the moving section, to provide an alarm
function, such as an incoming call notification.
Inventors: |
Yang; Tae-Heon; (Daejeon,
KR) ; Bae; Yu-Dong; (Suwon-si, KR) ; Kwon;
Dong-Soo; (Daejeon, KR) ; Lee; Young-Min;
(Yongin-si, KR) ; Lee; Eun-Hwa; (Suwon-si, KR)
; Lee; Jeong-Seok; (Suwon-si, KR) ; Pyo;
Dong-Bum; (Daejeon, KR) ; Cho; Young-Jun;
(Daejeon, KR) |
Assignee: |
Korea Advanced Institute Of Science
And Technology
Daejeon
KR
Samsung Electronics Co., Ltd.
Suwon-si
KR
|
Family ID: |
45975767 |
Appl. No.: |
13/279749 |
Filed: |
October 24, 2011 |
Current U.S.
Class: |
455/567 |
Current CPC
Class: |
H04M 1/00 20130101; H02K
33/16 20130101; G06F 3/016 20130101; G06F 3/04886 20130101; G08B
13/00 20130101; B06B 1/045 20130101 |
Class at
Publication: |
455/567 |
International
Class: |
H04W 68/00 20090101
H04W068/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 22, 2010 |
KR |
10-2010-0103662 |
Claims
1. A vibration module for a portable terminal, the vibration module
comprising: a housing; a magnetic moving part movable in a first
direction within the housing; an elastic member supported between
opposite ends of the magnetic moving part and inner walls of the
housing; and a solenoid coil provided in the housing.
2. The vibration module of claim 1, further comprising a pair of
yokes installed on the inner walls of the housing, wherein, in
response to a signal input to the solenoid coil, the magnetic
moving part vibrates in the first direction between the yokes while
being supported by the elastic member.
3. The vibration module of claim 2, wherein, in response to another
signal input to the solenoid coil, the magnetic moving part moves
from a position in which magnetic moving part contacts one of the
yokes to contact the other one of the yokes.
4. The vibration module of claim 2, wherein when the signal is not
input to the solenoid coil, the magnetic moving part remains in
contact with the one of the yokes.
5. The vibration module of claim 1, wherein the magnetic moving
part comprises: a first magnetic part positioned at one end of the
magnetic moving part with a south pole thereof arranged adjacent to
the solenoid coil and with a north pole thereof arranged away from
the solenoid coil; and a second magnetic part positioned at the
other end of the magnetic moving part with a north pole thereof
arranged adjacent to the solenoid coil, and with a south pole
thereof arranged away from the solenoid coil.
6. The vibration module of claim 5, wherein each of the first and
second magnetic parts has a pair of magnetic bodies arranged along
a second direction perpendicular to the first direction.
7. The vibration module of claim 6, wherein the magnetic moving
part further comprises a magnetic path member extending between the
pair of magnetic bodies of the first magnetic part, and between the
pair of magnetic bodies of the second magnetic part.
8. The vibration module of claim 5, wherein the magnetic moving
part further comprises a weight member having seating grooves
formed on one side thereof, with the first and second magnetic
parts positioned in respective seating grooves.
9. The vibration module of claim 8, wherein the weight member is
formed from tungsten.
10. The vibration module of claim 1, wherein the solenoid coil has
a core part arranged in the first direction and a coil part wound
around the core part, and wherein a pair of solenoid coils are
arranged along the first direction.
11. The vibration module of claim 10, wherein the magnetic moving
part comprises: a first magnetic part positioned at one end of the
magnetic moving part with a north pole arranged adjacent to a first
solenoid coil of the solenoid coils and a south pole arranged away
from the first solenoid coil; and a second magnetic part positioned
at an other end of the magnetic moving part with a south pole
arranged adjacent to a second solenoid coil and a north pole
arranged away from the second solenoid coil.
12. The vibration module of claim 10, further comprising an iron
piece arranged between the solenoid coils.
13. The vibration module of claim 10, wherein the first solenoid
coil and the second solenoid coil are arranged to generate
oppositely acting electromagnetic forces when a same input signal
is applied to each of the first solenoid coil and the second
solenoid coil.
14. The vibration module of claim 1, further comprising an
equilibrium member installed on a first inner wall of the housing
along the first direction, wherein an attraction force between the
magnetic moving part and the equilibrium member attenuates another
attraction force between the magnetic moving part and the solenoid
coil.
15. The vibration module of claim 1, wherein the magnetic moving
part comprises a weight member surrounding the solenoid coil and a
pair of first magnetic bodies provided on the weight member.
16. The vibration module of claim 15, wherein the magnetic moving
part further comprises a first magnetizable member provided on the
weight member surrounding the solenoid coil and the weight member,
and wherein the first magnetic bodies positioned on the first
magnetizable member.
17. The vibration module of claim 15, wherein the solenoid coil
comprises a core part arranged along the first direction and a coil
part wound around the core part, and wherein the core part has a
second magnetic body and second magnetizable members provided at
opposite ends of the second magnetic body, the second magnetic body
and the second magnetizable members being arranged along the first
direction.
18. The vibration module of claim 17, wherein the magnetic moving
part further comprises a first magnetizable member provided on the
weight member to wrap the solenoid coil together with the weight
member, and wherein when a signal is not input to the solenoid
coil, one side inner wall of the weight member comes into contact
with one end of the solenoid coil by the attraction force between
the second magnetic body and the first magnetizable member.
19. The vibration module of claim 17, wherein the magnetic moving
part further comprises a first magnetizable member provided on the
weight member to wrap the solenoid coil together with the weight
member, the first magnetizable member having protrusions extending
inwardly of inner walls of the weight member to face opposite ends
of the solenoid coil, wherein when a signal is not input to the
solenoid coil, one of the protrusions of the first magnetizable
member comes into contact with one of the opposite ends of the
solenoid coil by an attraction force between the second magnetic
body and the first magnetic member.
20. A magnetic vibration module for a portable terminal, the
magnetic vibration module comprising: a magnetic force generator;
and an electromagnetic force generator arranged parallel to the
magnetic force generator, wherein the magnetic force generator
reciprocates in response to an input signal applied to the
electromagnetic force generator.
21. The magnetic vibration module of claim 20, further comprising a
first magnetic path provided for passage of magnetic force
generated from the magnetic force generator; and a second magnetic
path provided for passage of magnetic force generated from the
magnetic generator, wherein the electromagnetic force generator
generates an electromagnetic force along the first and second
magnetic paths, and the magnetic force generator alternately uses
the first and second magnetic paths to linearly reciprocate when
the electromagnetic force generator generates the electromagnetic
force.
22. The magnetic vibration module of claim 21, further comprising a
limiter provided at opposite ends of a linear reciprocating section
of the magnetic force generator, respectively, wherein the magnetic
force generator hits the limiter to generate impact force while
reciprocating in the reciprocating section between the limiter.
23. The magnetic vibration module of claim 21, further comprising
an elastic member provided at each opposite end of the magnetic
force generator, wherein a resonance frequency of the magnetic
vibration module is based on mass of the magnetic force generator
and an elastic constant of the elastic member.
24. The magnetic vibration module of claim 21, wherein the first
and second magnetic paths are cores extending and arranged along a
reciprocating direction of the magnetic force generator, and the
electromagnetic force generator are coils wound around the
cores.
25. The magnetic vibration module of claim 24, wherein the first
and second magnetic paths are arranged to generate oppositely
acting electromagnetic forces.
26. The magnetic vibration module of claim 20, wherein the magnetic
force generator comprises a weight member and magnetic bodies
positioned on the weight member.
27. The magnetic vibration module of claim 26, wherein the weight
member is formed from tungsten.
28. The magnetic vibration module of claim 21, further comprising
an equilibrium member, wherein the magnetic force generator is
arranged between the first and second magnetic paths and the
equilibrium member, wherein an attraction force generated between
the magnetic force generator and the first and second magnetic
paths is counterbalanced by an attraction force generated between
the magnetic force generator and the equilibrium member.
Description
PRIORITY
[0001] This application claims priority under 35 U.S.C.
.sctn.119(a) to an application filed in the Korean Industrial
Property Office on Oct. 22, 2010, and assigned Serial No.
10-2010-0103662, the contents of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to a portable
terminal and, more particularly, to a vibration module for a
portable terminal, which can provide a haptic feedback
function.
[0004] 2. Description of the Related Art
[0005] Haptic feedback refers to a method for expressing
information based on a user's sense of touch and skin contact,
includes providing additional meaning by a force feedback function,
for example to remotely control a robot arm. Recently, efforts have
been made to utilize haptic feedback in portable terminals, such as
cellular phones, not only as a simple vibration function for a
incoming call notification, but also as a function for providing
notification that a signal value of a key selected by the user is
normally input when the user manipulates a touch screen.
[0006] In general, when there is a call request, i.e. an incoming
call, or when a text message is received, a portable terminal
provides a vibration mode as one of various methods to provide
notification of same. Operation in the vibration mode involves
operating a vibration motor of the portable terminal.
[0007] Considering the portability of portable terminals, a coin
type vibration motor or a cylinder or bar type vibration motor may
be employed as a vibration motor in a portable terminal. However,
such motors merely provide an incoming call notification
function.
[0008] Recently, with the appearance of touch screen phones, which
can provide a full-browsing screen when using the Internet or the
like, input devices, such as keypads, are implemented as virtual
keypads on touch screens. Such virtual keypads sense points
contacted by a user to input signal values allocated to the points,
respectively. A typical button-type keypad can provide a click
feeling to a user with dome switches or the like, so that the user
can recognize the manipulation of a keypad via sense of touch.
Therefore, a user skilled with portable terminal keypad data entry
can recognize whether figures and characters intended to be input
by key manipulation are indeed being input without having to
visually confirm that the figures and characters being entered by
manipulation appear on a display of the portable terminal. However,
when manipulating a keypad implemented on a touch screen, the user
must directly confirm the input values through a display device
since a click feeling cannot be provided like that provided by a
button type keypad with dome switches.
[0009] As a result, efforts are being made to provide a haptic
feedback function to portable terminals equipped with a touch
screen type input device to enhance convenience and allow a user to
avoid having to confirm input values by viewing a display device.
Such a haptic function for a portable terminal is implemented by
operating a vibration motor when a touch screen is manipulated.
[0010] However, conventional coin type, cylinder type and bar type
vibration motors are limited in implementing the haptic feedback
function due to lengthy response time thereof. That is, since a
residual vibration time interval of a coin type motor, a cylinder,
or a bar type vibration motor is long, a difficulty arises when
recognizing via sense of touch whether signal values of keys
manipulated by the user are correctly input, particularly when a
user rapidly and continuously inputs various keys. A time interval
of a vibration motor is a complete operation cycle, which includes
a time during which operation of the motor continues due to
inertia, until the motor completely stops.
[0011] Linear motors with low power consumption and high
reliability have been proposed as vibration motors, with improved
short response time. However, such conventional linear motors have
disadvantages of having a single resonance frequency and abruptly
reduced vibration power, even if an operating frequency deviates
only about 2 to 3 Hz from the resonance frequency. Such
conventional linear motors can sufficiently provide an alarm
function, such as an incoming call notification, when operated
within its resonance frequency. However, such conventional linear
motors are also limited in providing the haptic feedback function
since due to low response velocity. That is, the linear motor can
provide sufficient vibration power after about 30 ms from the time
point that an input signal is applied, and the vibration caused by
inertia can be completely terminated after about 50 ms from the
instant the input signal is interrupted.
[0012] Therefore, although the incoming call notification function
can be sufficiently conducted using existing linear motors, there
is a limit in providing the haptic feedback function for confirming
accurate manipulation of a touch screen.
SUMMARY OF THE INVENTION
[0013] Accordingly, the present invention has been made to solve
the above-mentioned problems occurring in the conventional systems,
and an aspect of the present invention provides a vibration module
for a portable terminal, improved to have short response time, to
provide a more effective click feeling and haptic feedback function
even during time of rapid, continuous key input operation via a
touch screen.
[0014] Another aspect of the present invention provides a vibration
module for a portable terminal to generate various haptic patterns
corresponding to touch screen operations, such as drag, as well as
providing a click feeling similar to a button click feeling at the
time of key input through a touch screen.
[0015] Yet another aspect of the present invention provides a
vibration module for a portable terminal to provide sufficient
vibration power in terms of an alarm function, such as an incoming
call notification, as well as providing a good haptic feedback
function.
[0016] In accordance with an aspect of the present invention, there
is provided a vibration module for a portable terminal, including a
housing, a magnetic moving part installed to be movable in a first
direction within the housing, elastic members supported between the
opposite ends of the magnetic moving part and inner walls of the
housing, respectively, and a solenoid coil provided in the
housing.
[0017] In accordance with another aspect of the present invention,
a magnetic vibration module is provided for a portable terminal,
with the magnetic vibration module including a magnetic force
generator, and an electromagnetic force generator arranged parallel
to the magnetic force generator, wherein the magnetic force
generator reciprocates in response to an input signal applied to
the electromagnetic force generator.
[0018] The vibration modules as described above are preferably
positioned at either end of a moving section due to the magnetic
force between the magnetic moving part and an object surrounding
the magnetic moving part. Therefore, in response to an input signal
applied to solenoid coil(s), the vibration module moves from a
position at one of the opposite ends of the moving section to
another position at another end of the moving section. As a result,
the vibration module provides a user with a feeling similar to a
click feeling, via an acceleration that is produced at an instant
of stopping of the vibration module. In addition, when vibrating,
the vibration module generates sufficient vibration power by
acceleration at an instant of changing a moving direction at the
ends of the moving section, thereby providing an alarm function,
such as an incoming call notification. Further, if the amplitude of
the magnetic moving part is limited by use of yokes or the like,
the magnetic moving part can hit the yokes to generate impacts at
the instant of arrival at the ends of the moving section, to
generate vibration for implementing a click feeling or an haptic
feedback function in other various patterns.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The above and other aspects, features and advantages of the
present invention will be more apparent from the following detailed
description taken in conjunction with the accompanying drawings, in
which:
[0020] FIGS. 1A to 1C describe operation of a conventional
vibration module;
[0021] FIGS. 1D to 1F describe operation of a vibration module for
a portable terminal in accordance with the present invention;
[0022] FIG. 2 is an exploded perspective view showing a vibration
module for a portable terminal in accordance with an embodiment of
the present invention;
[0023] FIG. 3 is a perspective view showing the vibration module of
FIG. 2 in the assembled state;
[0024] FIGS. 4A to 4C describe the operation of the vibration
module of FIG. 2;
[0025] FIGS. 5A to 5D describe the operating mechanism of the
vibration module of FIG. 2;
[0026] FIG. 6 is a graph showing a frequency response
characteristic of the vibration module of FIG. 2;
[0027] FIG. 7 is a graph showing the response time measured for the
vibration module of FIG. 2;
[0028] FIGS. 8A to 8C are graphs showing measured vibration
acceleration of the vibration module of FIG. 2;
[0029] FIG. 9 is a graph showing measured vibration acceleration at
a resonance frequency of the vibration module of FIG. 2; and
[0030] FIG. 10 is a top plan view showing a vibration module for a
portable terminal in accordance with another embodiment of the
present invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE PRESENT INVENTION
[0031] Hereinafter, embodiments of the present invention will be
described with reference to the accompanying drawings. In the
following description, the same elements will be designated by the
same reference numerals although they are shown in different
drawings. Further, in the following description of the present
invention, a detailed description of known functions and
configurations incorporated herein will be omitted when it may make
the subject matter of the present invention rather unclear.
[0032] FIGS. 1A to 1C schematically show the operating principle of
a conventional linear motor, and FIGS. 1D to 1F schematically show
the operating principle of a vibration module for a portable
terminal in accordance with the present invention.
[0033] As shown in FIG. 1A, when the conventional linear motor
operates, the vibration gradually strengthens, thereby limiting a
rapid response of the linear motor. In addition, it is difficult
for the linear motor to produce a haptic pattern corresponding to a
rapid and continuous key input due to vibration caused by inertia,
even after interruption of an input signal.
[0034] In addition, in such conventional linear motor, the vibrator
tends to move toward a central position away from opposite ends of
a linear reciprocating section, i.e. toward a neutral position
shown in FIG. 1B, at which position the conventional vibrator
remains in a stable stopped state. When vibrated, the conventional
vibrator has a highest velocity at the neutral position, and the
velocity is gradually reduced as the vibrator approaches either
opposite end of the linear reciprocating section, as shown in FIG.
1C, whereby the conventional linear motor cannot produce a
sufficiently high vibration power. Therefore, it is difficult to
implement an alarm function, e.g. an incoming call notification,
with such conventional linear motor.
[0035] In contrast, the vibration module of the present invention
provides a vibrator having an unstable state at the neutral
position, as shown in FIG. 1E, thereby tending to move toward one
opposite end of the reciprocating section. Therefore, as shown in
FIG. 1F, the vibrator moves to either of the opposite ends of the
reciprocating section while being gradually accelerated, thereby
producing an acceleration at an instant of changing a moving
direction of the vibrator at the opposite ends of the reciprocating
section that is sufficient to provide an alarm function, such as an
incoming call notification. Moreover, since the vibrator is
installed within a confined space, the vibrator may hit the walls
of the space at the opposite ends of the reciprocating section,
thereby producing higher impact force.
[0036] The vibration module is implemented with a magnetic force
generator and an electromagnetic force generator. That is, the
electromagnetic force is generated in response to a signal input to
the electromagnetic force generator, and the magnetic force of the
magnetic force generator interact to linearly reciprocate the
electromagnetic force generator.
[0037] If the magnetic force generator is formed with a fixed
magnetic path, the vibration module can effectively use the
magnetic force of the magnetic force generator. The magnetic path
is provided by first and second magnetic paths, and constant
magnetic forces are produced in the first and second magnetic paths
according to input signals applied to the electromagnetic force
generator. At this time, the electromagnetic forces produced in
respective first and second magnetic paths preferably act opposite
to each other.
[0038] At the neutral position, the magnetic force generator forms
a magnetic path which passes both of the first and second magnetic
paths. However, if an input signal is input to the electromagnetic
force generator, the first and second magnetic paths produce
electromagnetic forces acting opposite to each other, which causes
the magnetic force generator to move toward either of the first and
second magnetic paths.
[0039] At this time, it is possible to switch the directions of the
electromagnetic forces produced by the first and second magnetic
paths by controlling the input signals applied to the
electromagnetic force generator, which consequently allows the
magnetic force generator to alternately use the first and second
magnetic paths. As a result, the magnetic force generator can
linearly reciprocate. This can be accomplished by arranging the
first and second magnetic paths along the magnetic force generator
moving direction.
[0040] The first and second magnetic paths can be implemented using
a core extending along the magnetic force generator moving
direction, in which case the electromagnetic force generator can be
implemented by winding a coil around the core.
[0041] At this time, since the attraction force between the first
and second magnetic paths and the magnetic force generator may be
an obstacle to the reciprocation of the magnetic force generator,
it is desired to provide a separate equilibrium member and to
arrange the magnetic force generator between the first and second
magnetic paths and the equilibrium member. As such, the attraction
force between the equilibrium member and the magnetic force
generator will counterbalance the attraction force between the
first and second magnetic paths and the magnetic force
generator.
[0042] If the limiters are arranged at the opposite ends of the
linear reciprocating section of the magnetic force generator,
respectively, the magnetic force generator hits the limits while
reciprocating between the limits, thereby generating impact force.
The impact force produced thereby can be usefully employed for
implementing an alarm function, such as an incoming call
notification, in a portable terminal.
[0043] In addition, if elastic members are provided at the opposite
ends of the magnetic force generator, it is possible to set a
resonance frequency by using the elastic constant of the elastic
members. The resonance frequency may be set in accordance with the
mass of the magnetic force generator. If the magnetic force
generator reciprocates at the resonance frequency, it is possible
to additionally strengthen the vibration power or the impact force
produced at the opposite ends of the reciprocating section.
[0044] FIGS. 2 through 10 show specific embodiments of the present
invention.
[0045] As shown in FIGS. 3 and 10, within a housing 101 or 201, the
vibration module 100 or 200 for a portable terminal includes a
solenoid coil 102 or 202 arranged in a stator form, the solenoid
coil serving as an electromagnetic force generator and forming a
magnetic path; and a magnetic moving part 103 or 203 arranged in a
vibrator form as magnetic force generator, the magnetic moving part
103 or 203 being supported by elastic members 104 within the
housing 101 or 201. As a result, the magnetic moving part 103 or
203 is vibrated in the housing 101 or 201 in response to a signal
input to the solenoid coil 102 or 202 while being supported by the
elastic members 104. Although the term `vibration` generally means
that an object is shaken and moved, as used herein `vibration`
indicates regular reciprocation of the vibrator in a predetermined
section or moving of the vibrator from one of the opposite ends of
the section to the other.
[0046] The solenoid coil 102 or 202 is anchored in the housing 101
or 201, and the magnetic moving part 103 or 203 is installed to be
movable in the first (X) direction in the housing 101 or 201. In
the first (X) direction, the elastic members 104 are interposed
between the internal walls of the housing 101 or 201 and the
opposite ends of the magnetic moving part 103 or 203, respectively.
That is, the magnetic moving part 103 or 203 is installed to
reciprocate in the first (X) direction while being supported by the
elastic members 104. If an input signal is applied to the solenoid
coil 102 or 202, the magnetic moving part 103 or 203 vibrates
within the housing 101 or 201 due to an interaction between a
magnetic force of the magnetic moving part and magnetic forces
produced by the solenoid coil 102 or 202.
[0047] At this time, as shown in FIG. 2, a pair of solenoid coils
102 may be arranged along the first (X) direction, and if the same
input signals are applied to each coil of the pair of solenoid
coils, the electromagnetic forces produced by the solenoid coils
102 act opposite to each other.
[0048] As shown in FIG. 4a, when a signal is not applied to the
solenoid coils 102, the magnetic moving part 103 forms a common
magnetic path with the solenoid coils 102 at the central point
(hereinafter referred to as a "neutral point") of the moving
section. However, if the same input signals are applied to the
solenoid coils 102, the magnetic moving part 103 is moved toward
one of the solenoid coils 102 which provides attraction force,
thereby being positioned as shown in either FIG. 4B or FIG. 4C.
[0049] If yokes 125 are provided adjacent to the opposite ends of
the magnetic moving part 103 in the housing 101, as shown in FIG.
2, the magnetic moving part 103 can be moved toward one of the
yokes 125 by the magnetic force between the magnetic bodies in the
magnetic moving part 103 and the yokes, even if small external
force is applied or shaking is caused at the neutral point. The
embodiment shown in FIG. 2 illustrates that the yokes 125 are
arranged on the solenoid coils 102, respectively, which will be
described in more detail below. If the magnetic moving part 203 is
formed to wrap the solenoid coil 202, it may be possible to
incorporate a magnetic body 221a within the solenoid coil 202
itself and to add a configuration to perform the role of the yokes
to the magnetic moving part 203, as described below and shown in
FIG. 10.
[0050] Consequently, in the vibration module 100 or 200 for a
portable terminal, the magnetic moving part 103 or 203, which is a
vibrator, does not remain in a stable state at the neutral point,
and tends to move to one side of the moving section even with
minute shaking. Therefore, in a state in which the vibration module
100 or 200 is mounted in a real product, the magnetic moving part
103 or 203 is positioned at one side of the moving section rather
than at the neutral point, and vibrates or moves to the other side
of the moving section, in response to a signal applied to the
solenoid coil 102 or 202, more specifically, depending on the
frequency of an input signal.
[0051] As shown in FIGS. 2 and 3, the housing 101 has a receiving
space formed in the inside thereof, and is opened at one side. The
opened side of the housing 101 is closed by a separate cover member
101a. Among the inner walls of the housing, seating faces 113 are
formed on a pair of opposite inner walls. Yokes 125 are attached
and anchored on respective seating faces 113, with the yokes
further described below. In addition, a plurality of slits 117a and
117b are formed in the housing 101 for installation of the elastic
members 104, or paths for wiring a flexible printed circuit board
119 (FIG. 2) or the like.
[0052] A solenoid coil 102 includes a core part 121 arranged to
extend along the first (X) direction, and a coil part 123 wound
around the core part 121, wherein a pair of such solenoid coils 102
are arranged within the housing along the first (X) direction. When
no signal is applied to the coil parts 123, the core part 121 forms
a magnetic path with the magnetic moving part 103. If an input
signal is applied to the coil parts 123, a magnetic path is formed
biased to one of the coil parts 123, with the magnetic moving part
103. The core part 121 forming the magnetic path with the magnetic
moving part 103 can be controlled by the input signal applied to
the coil parts 123. Through this, the magnetic moving part 103
forms a magnetic path alternately with the core part 121 to produce
linear reciprocating force.
[0053] A central yoke 127 may be arranged between the solenoid
coils 102, wherein the yokes 125 are arranged between the ends of
the solenoid coils 102 and the inner walls of the housing 101,
respectively. The yokes 125 may be anchored to the seating faces
113, respectively.
[0054] In an embodiment of the present invention, the winding
direction of the left solenoid coil 102 is opposite to that of the
right solenoid coil 102, thereby producing electromagnetic forces
acting opposite to each other when a same input signal is applied
to the solenoid coils 102. As a result, when the same input signal
is applied to the solenoid coils 102, the magnetic moving part 103
produces an attraction force with one of the solenoid coils 102,
and a repulsion force in relation to the other solenoid coil
102.
[0055] The magnetic moving part 103 has a weight member 131 and
magnetic bodies 133a and 133b. In the present embodiment, two pairs
of magnetic bodies 133a and 133b are provided, with the magnetic
bodies arranged at the left side being referred to herein as a
"first magnetic part" and the magnetic bodies arranged on the other
side being referred to herein as a "second magnetic part" for the
convenience of description. The first magnetic part includes a pair
of magnetic bodies 133a arranged adjacent to the solenoid coils
102. The second magnetic part includes a pair of magnetic bodies
133b arranged away from the solenoid coils 102. Although the
present embodiment exemplifies a configuration that each of the
first and second magnetic parts includes a pair of magnetic bodies,
it is possible to configure each of the first and second magnetic
parts with a single magnetic body. In such a case, if the weight
member 131 is made in a shape similar to that shown in FIGS. 2 and
3, each of the magnetic bodies of the first and second magnetic
parts will have a shape extending in the second (Y) direction
perpendicular to the first (X) direction.
[0056] The weight member 131 can provide sufficient vibration power
when the vibration module is operated by increasing the weight of
the magnetic moving part 103. Therefore, the weight member 131 is
preferably manufactured using tungsten or an alloy thereof, which
has the heaviest weight per unit mass. The weight member 131 is
provided with seating grooves 131a for arranging the magnetic
bodies 133a and 133b. In addition, protrusions 131c are formed
between the seating grooves 131a arranged in the first (X)
direction, respectively, and another seating groove 131b extends
between the grooves 131a arranged in the second (Y) direction and
between the protrusions 131c. In the seating groove 131b, a
magnetic path member 135, such as an iron core, may be arranged.
The magnetic path member 135 extends in the first (X) direction.
The magnetic path member 135 stably forms a magnetic path between
the magnetic bodies 133a and 133b, thereby strengthening the
magnetic forces produced by the magnetic bodies 133a and 133b.
[0057] In arranging the magnetic bodies 133a and 133b, the magnetic
bodies 133a and 133b are positioned so that south poles (S-poles)
thereof are arranged adjacent to the solenoid coil 102, and north
poles (N-poles) thereof are arranged away from the solenoid coil
102. In addition, the magnetic bodies of the second magnetic part
are arranged with the N-poles thereof are arranged adjacent to the
solenoid coil 102, and the S-poles thereof are arranged away from
the solenoid coil 102. Of course, the polarities of the magnetic
bodies may be reversely arranged in relation to the above-mentioned
arrangement.
[0058] As such, the vibration module 100 also forms a magnetic path
M as shown in FIG. 4 in the interior thereof. That is, the magnetic
path M extends along the magnetic bodies 133a and 133b, and the
core parts 121 of the solenoid coils 102 is formed.
[0059] In order to form the stable magnetic path M within the
vibration module 100, and to mitigate the attraction force between
the magnetic moving part 103 and the core parts 121 so that the
movement of the magnetic moving part 103 in the first (X) direction
can be smoothly conducted, an equilibrium member 149 may be
provided in the vibration module 100. On an inner wall of the
housing 101 opposite to one side of the magnetic moving part 103 in
the second (Y) direction, an anchoring groove 115 is formed, in
which the equilibrium member 149 is installed. As such, among the
magnetic bodies 133a of the magnetic moving part 103, one pair is
arranged adjacent to the equilibrium member 149, and an other pair
is arranged adjacent to the core parts 121.
[0060] The equilibrium member 149 and the core parts 121 may be
manufactured from a magnetizable material, e.g. steel, to produce
an attraction force with the magnetic bodies 133a and 133b. As
such, the attraction force acting between the magnetic moving part
103 and the core part 121 can be attenuated by the attraction force
acting between the magnetic moving part 103 and the equilibrium
member 149. As a result, the magnetic moving part 103 can move in
the first (X) direction without being biased to one side in the
second (Y) direction between the solenoid coils 102 and the
equilibrium member 149 while being supported by the elastic members
104. That is, the elastic members 104 are installed between the
magnetic moving part 103 and the inner walls of the housing to
limit the movement of the magnetic moving part 103 in the second
(Y) direction. As a result, the magnetic moving part 103 can move
in the first (X) direction without being attached to the
equilibrium member 149 and the core part 121.
[0061] The elastic members 104 interconnect the magnetic moving
part 103 and the housing 101, to float the magnetic moving part 103
in the housing 101. In addition, since the elastic members 104 have
their own resonance frequency, they will intensively vibrate the
magnetic moving part 103 when an input signal corresponding to the
resonance frequency of the elastic members 104 is applied to the
solenoid coil 102. The opposite ends of each elastic members 104
have free ends 141 and 143 which are bent to have shapes to be
anchored to the housing 101 and the magnetic moving part 103,
respectively, and the free ends 141 and 143 are interconnected by
an elastic element 145.
[0062] Free end 141 is bound to the housing 101 through a slit 117a
formed in the housing 101, and anchored to wrap an inner wall and
an outer wall of the housing 101. The other free end 143 takes a
shape bent to face a part of the outer face of one of the opposite
ends of the magnetic moving part 103 and the equilibrium member
149, and to wrap the part of the outer face. The elastic element
145 preferably extends in a zigzag shape, and generally takes a "V"
shape when seen from a top plan view. When the magnetic moving part
103 is vibrated, the elastic element 145 can be deformed to such an
extent that it is positioned nearly in a single plane. However, if
the displacement of the magnetic moving part 103 is limited, the
elastic element 145 may not be positioned substantially in a single
plane. Meanwhile, each of the elastic members 104 may be formed
only by the elastic element 145 without having the free ends 141
and 143. In such a case, the opposite ends of the elastic members
104 may be attached to the magnetic moving part 103 and the inner
walls of housing 101 through welding or the like, respectively.
[0063] As described above, in the vibration module 100, an input
signal, i.e. electric current, is applied to the solenoid coils 102
through the flexible printed circuit board 119. As shown in FIG. 2,
the flexible printed circuit board 119 is positioned on the inside
of the housing 101, attached via slit 117b formed in the housing
101, and connected to the solenoid coils 102.
[0064] Referring to FIG. 4 again, the yokes 125 arranged at the
ends of the solenoid coils 102 can limit the displacement of the
magnetic moving part 103. That is, the yokes 125 are arranged to
interfere with the magnetic moving part 103 at the opposite ends of
the moving section of the magnetic moving part 103. As such, if the
magnetic moving part 103 moves, the yokes 125 periodically contact
with the magnetic moving part 103, thereby producing impact force,
and if the magnetic moving part 103 is periodically vibrated, the
impact force will be regularly produced.
[0065] If an input signal is not applied to the solenoid coils 102,
it is difficult for the attraction force between the core parts 121
of the solenoid coils 102 and the magnetic moving part 103 to keep
the magnetic moving part in the stopped state at the neutral point.
Furthermore, if the yokes 125 are provided, the attraction force
between the magnetic moving part and the yokes 125 acts more
strongly, which causes the magnetic moving part 103 to be more
instable at the neutral point. Consequently, if an input signal is
not applied to the solenoid coils 102, the magnetic moving part 103
remains at one end of the moving section, and more particularly, in
contact with one of the yokes 125.
[0066] Operation of the vibration module 100 is described in
further detail with reference to FIGS. 5A to 5D. FIGS. 5a to 5c
show magnetic paths formed depending on the position of the
magnetic moving part 103 and moving directions, and FIG. 5D shows a
graph showing forces produced in accordance with the position of
the magnetic moving part 103.
[0067] In FIG. 5D, the horizontal axis corresponds to the position
of the magnetic moving part 103 in the first (X) direction, and the
vertical axis corresponds to the forces acting on the magnetic
moving part 103. Here, a force having a positive (+) value acts to
move the magnetic moving part 103 rightward, and a force having a
negative (-) value acts to move the magnetic moving part 103
leftward.
[0068] In addition, the curve designated by `M` in FIG. 5D
indicates forces acting on the magnetic moving part 103 when only
the magnetic moving part 103 and the yokes 124 are provided, the
curve designated by `S` indicates forces acting on the magnetic
moving part 103 when the elastic members 104 are provided together
with the magnetic moving part 103 and the yokes 125, and the curves
designated by `C1` and `C2` indicate forces acting on the magnetic
moving part 103 by electromagnetic forces from the magnetic moving
part 103, the yokes 125, the elastic members 104, and the solenoid
coils 102 when input signals are applied to the solenoid coils
102.
[0069] Under the premise that the magnetic moving part 103 is
arranged to be movable only in the first (X) direction, if only the
solenoid coils 102, the yokes 125 and the magnetic moving part are
arranged in the housing 101, the magnetic moving part 103 tends to
move to one end of the moving section. Although the force acting on
the magnetic moving part 103 has a zero (0) value, the magnetic
moving part 103 will move leftward or rightward since it is
inevitable that a small force will act on the magnetic moving part
103. Since the attraction force between the core parts 121 and the
magnetic moving part 103 acts even if the yokes 125 are not
provided, it is impossible for the magnetic moving part 103 to
remain in the stable state at the neutral point.
[0070] If the elastic members 104 with the same elastic constants
and specifications are arranged at the opposite ends of the
magnetic moving part 103, the force acting on the magnetic moving
part 103 may be somewhat alleviated depending on the position of
the magnetic moving part 103.
[0071] In addition, if an input signal is applied to the solenoid
coil 102, the magnetic moving part 103 moves from left to right, or
from right to left, with FIGS. 5A to 5C showing a process in which
the magnetic moving part 103 moves from left to right. The magnetic
paths formed by the magnetic moving part 103 generally follow a
clockwise pattern. However, by changing the polarities of the
magnetic bodies 133a and 133b arranged in the magnetic moving part
103, the direction of the magnetic paths can be changed.
[0072] By the input signals applied to the solenoid coils 102, the
left solenoid coil 102 generates electromagnetic force E2 (in FIG.
5A) in a direction opposite to the magnetic path of the magnetic
moving part 103, and the right solenoid coil 102 generates
electromagnetic force in the direction equal to the magnetic path
of the magnetic moving part 103. Therefore, the magnetic moving
part 103 moves rightward. At this time, the `C1` curve indicates
the forces for moving the magnetic moving part 103 from left to
right when input signals are applied to the solenoid coils 102, and
the `C2` curve indicates the forces for moving the magnetic moving
part 103 from right to left when input signals are applied to the
solenoid coils 102.
[0073] Referring to the `C1` and `C2` shown in FIG. 5D, the forces
for substantially moving the magnetic moving part 103 in the
vibration module 100 are strengthened as the magnetic moving part
103 moves toward either opposite end of the moving section.
[0074] The term, "left" or "right" used in describing the operating
mechanism of the vibration module 100 with reference to FIG. 5
generally indicates any one of the opposite ends of the moving
section of the magnetic moving part 103.
[0075] Meanwhile, if limiters for the moving section of the
magnetic moving part 103, for example, the yokes 125 are arranged
at the opposite ends of the moving section of the magnetic moving
part 103 to limit the moving section of the magnetic moving part
103, an impact force is produced when the magnetic moving part 103
is vibrated, thereby providing vibration capable of being felt by a
user. At this time, as the magnetic moving part 103 approaches
either end of the moving section of the magnetic moving part 103,
the forces acting on the magnetic moving part 103 are gradually
increased. Therefore, the impact force produced when the magnetic
moving part 103 hits the yokes 125 will have an intensity
sufficient to provide a haptic feedback function. In addition, if a
resonance frequency is established by arranging the elastic members
104 between the magnetic moving part 103 and the housing 101, a
high resonance vibration power is generated at the corresponding
frequency to perform the alarm function of a portable terminal, as
discussed below.
[0076] A result obtained by measuring the frequency response
characteristic of the vibration module 100 configured as described
above is shown in FIG. 6, which shows a frequency response
characteristic in accordance with the change of input signals in
terms of frequency when the same input signals are applied to the
solenoid coils 102 with input voltages of .+-.3.3 V, respectively.
As seen from FIG. 6, the vibration module 100 produces a vibration
acceleration of about 2.5 G (with G being the constant of gravity)
for the input signals less than 100 Hz, and produces a vibration
acceleration of about 3.5 G at the input signal of 100 Hz, which is
the resonance frequency. Therefore, it is possible to vibrate the
magnetic moving part 100 in various patterns by applying various
frequencies less than 100 Hz as the input signals, to produce
various haptic patterns.
[0077] Meanwhile, the resonance frequency of the vibration module
100 can be adjusted depending on the elastic constant of the
elastic members 104. For example, if the elastic members 104 with
an elastic constant of 266 N/m are employed, the resonance is
adjusted to approximately 80 Hz.
[0078] FIG. 7 is a graph showing a result obtained by measuring the
response time of the vibration module 100 by applying an input
signal (I) of 5V, 1 Hz to the solenoid coil. A time delay of the
vibration module 100 is a time interval required to produce
vibration or impact after the input signal (I) is applied to the
solenoid coil 102 and the vibration module is operated. As shown, a
time delay of the vibration module 100 of only 6.6 ms is obtained.
In comparison, for a linear motor employed in a conventional
portable terminal, approximately 30 ms is required for the linear
motor to arrive at resonance frequency after an input signal is
applied, and vibration acceleration is about 1.5 Grms (root mean
square). Furthermore, such conventional linear motor requires about
50 ms until for vibration to stop after the input signal is
interrupted.
[0079] FIG. 7 shows that the vibration module 100 has a
substantially rapid response time, and substantially does not
provide residual vibration, i.e. resonance until the vibration is
completely stops after an input signal interruption.
[0080] FIGS. 8A to 8C show results `O` obtained by measuring
produced vibration accelerations while varying the frequencies of
the input signal `I` to the vibration module 100. FIG. 9 shows
results `O` obtained by measuring the vibration accelerations of
the vibration module 100 when a resonance frequency of 100 Hz is
used as the input signal `I`.
[0081] As shown in FIGS. 8A to 8C and FIG. 9, since each of the
waveforms of vibration accelerations of the vibration module 100
takes an impulse waveform, there exists substantially no time
interval until the vibration module arrives at the resonance after
an input signal is applied, or until vibration completely stops
after the input signal interruption. In addition, since each of the
vibration waveforms of the vibration module taking an impulse
waveform is substantially identical to the frequencies of its input
signal, it is possible to freely control the frequencies of the
input signal from zero (0) to the resonance frequency to generate
various haptic patterns. Furthermore, since the vibration
accelerations of the vibration module 100 are substantially higher
than those of conventional linear motors, the vibration module 100
can sufficiently provide both a haptic feedback function and a
conventional alarm function, e.g. an incoming call notification or
the like even if an input signal with a resonance frequency is not
applied. However, in order to differentiate the time interval for
operating the vibration module with a haptic feedback function from
the time interval for operating the vibration module with an alarm
function, the vibration module is preferably set that the alarm
function, such as an incoming call notification, is executed at the
resonance frequency.
[0082] In addition, if an input signal is input so that the
vibration module impacts only once, the magnetic moving part 103
will hit one of the yokes 125 to produce impact, which can be
usefully used for providing a click feeling to a user when the user
inputs figures or characters.
[0083] FIG. 10 is a top plan view showing a vibration module 200 in
accordance with another embodiment of the present invention. As
compared to the previous embodiment, the vibration module 200 in
accordance with the present embodiment has a solenoid coil 202 and
magnetic moving part 203 that are different from those of the
previous embodiment in terms of construction but are similar to the
previous embodiment in terms of operation and response
characteristic. Therefore, the following description focuses on the
construction of the solenoid coil 202 and the magnetic moving part
203.
[0084] The solenoid coil 202 is anchored to the housing 201,
wherein the solenoid coil 202 is arranged at a central area of the
bottom of the receiving space. The solenoid coil 202 includes a
core part, and a coil part 223 is wound on an outer periphery of
the core part, the core part includes a magnetic body 221a and
magnetizable members 221b arranged along the first (X) direction.
The magnetizable members 221b are arranged at opposite ends of the
magnetic body 221a.
[0085] The magnetic moving part 203 includes a weight member 231
arranged to surround the solenoid coil 202, and additional magnetic
bodies 233 arranged on the weight member 231. A magnetic body 233
is arranged adjacent to each of the four corners of the weight
member 231, and an additional magnetizable member 235 is arranged
on the weight member 231 to form a magnetic path M, as shown in
FIG. 10. The additional magnetizable members 235 are arranged to
surround the solenoid coil 202, together with the weight member
231.
[0086] The magnetic bodies 233 and the additional magnetizable
member 235 arranged on the magnetic moving part 203 are also
referred to herein as "first magnetic bodies" and "first
magnetizable members," respectively, and the magnetic bodies 221a
and the magnetizable members 221b of the core part are also
referred to as "second magnetic bodies" and "second magnetizable
members," respectively. The first magnetic bodies 233 are
positioned so that the polarities thereof are arranged along the
first (X) direction, and the second magnetic bodies 221a are
positioned so that the polarities thereof are arranged opposite to
those of the first magnetic bodies 233. As such, two magnetic paths
M are formed in the vibration module 200. Meanwhile, each of the
first magnetizable members 235 has a protrusion, which extends
inwardly of the corresponding inner wall of the weight member 231
to face the opposite ends. The second magnetizable members 221b and
first magnetizable member 235 may be selectively magnetized in
accordance with the electric current applied to the solenoid coil
202 or the magnetic bodies 221a and 233.
[0087] In the embodiment of FIG. 10, since repulsive forces act
between the first and second magnetizable members 235 and 221b, and
attraction forces act between the protrusions of the first
magnetizable members 235 and the second magnetic bodies 221a, the
magnetic moving part 203 is stable at the neutral point. However,
as in the previous embodiment, the magnetic moving part 203 moves
toward either of the opposite ends of the moving section by minute
shaking or the like. Therefore, the inner walls of the magnetic
moving part 203, in particular the protrusion portions of the first
magnetizable members 235 come into contact with either end of the
solenoid coil 202. A person skilled in the art will appreciate that
if sufficient attraction forces can be produced between the first
magnetizable members 235 and the second magnetic bodies 221a even
if the first magnetizable members 235 do not have protrusions
extending inwardly of the inner walls of the weight member 231,
making it unnecessary to form protrusions on the first magnetizable
members 235.
[0088] In the vibration module 200 configured as described above,
the magnetic moving part 203 also moves from left to right or from
right to left, or reciprocates within a moving section of a
predetermined extent, depending on an input signal applied to the
solenoid coil 202.
[0089] Consequently, a magnetic moving part is positioned at one
side of the moving section by an attraction force between the
magnetic moving part and a yoke or an attraction force between the
magnetic moving part and a solenoid coil. In response to an input
signal applied to the solenoid coil, the magnetic moving part moves
from one side to the other side, or reciprocates within the moving
section, thereby producing a predetermined impact or shock
wave-type vibration. Such an impact or shock-wave type vibration
can provide various haptic patterns when a user manipulates a
portable terminal through a virtual input device implemented on a
screen of the portable terminal. In addition, the impact or shock
wave-type vibration can provide various feelings when playing a
game, as well as when performing an input action, thereby providing
sense of reality.
[0090] While the invention has been shown and described with
reference to certain embodiments thereof, it will be understood by
those skilled in the art that various changes in form and details
may be made therein without departing from the spirit and scope of
the invention as defined by the appended claims.
* * * * *